Field of the Invention
The present invention relates to improvements in methods of and apparatus for sampling, processing and collecting tissue samples using aspiration processes.
Brief Description of the State of Knowledge in the Art
There are many applications where human tissue is harvested, processed and transplanted back into human beings for various cosmetic, reconstructive and biomedical reasons.
In general, there are various types of human tissue involved in such transplantation procedures, including autologous and allogeneic forms of adipose (i.e. fat) and musculoskeletal (i.e. bone, ligament, cartilage and skin) tissue, for use in autografting and allografting.
Also, in recent times, public confidence in and comfort with synthetic materials (e.g., silicone and teflon) and foreign tissues (e.g., bovine collagen) has declined. Conversely, the interest in and demand for autologous adipose tissue transplantation has risen.
Typically, autologous adipose tissue transplantation involves the procurement of adipose tissue by liposuction techniques from an area of abundance, and re-injection of the harvested adipose tissue into a different site of the same individual for cosmetic/reconstructive augmentation or enhancement purposes.
Generally, adipose tissue must be as ‘clean’ or refined as possible before re-introduction to maximize the chances of graft survival. Such refinement preferably is done with as little exposure of the tissue to air as possible (i.e., “anaerobic tissue handling”).
Unfortunately, the nature of conventional liposuction procedures have precluded easy tissue isolation after initial harvest (especially on a large scale) because the volume and/or viscosity of ‘raw’ liposuction effluent also contains unwanted components, e.g., oil, blood and anesthetic solution.
Currently, there are no standard techniques, methods, or devices that exist for the simple, large scale isolation and refinement of liposuction-harvested adipose tissue. Although cannulas, needles and methods for tissue harvest and preparation exist, these techniques are tedious, inefficient and require a pseudo-sterile centrifugation step.
Several devices exist for the isolation of certain cells.
For example, U.S. Pat. Nos. 5,035,708 and 5,372,945, issued to Alchas et al., describe an endothelial cell procurement and deposition kit and a device and method for collecting and processing fat tissue and procuring microvessel endothelial cells to produce endothelial cell products.
U.S. Pat. No. 6,316,247 to Katz et al discloses a method of and apparatus for separating adipose tissue for autologous tissue transplantation. Liposuctioned tissue removed from the patient is transferred into the device through the inlet port that is contiguous with the inner flexible porous container. Pieces of adipose tissue are “trapped” within the inner flexible container whereas waste components (free oil, blood, serum) are able to drain through the pores and out the outlet port. After all the desired liposuction effluent is transferred, the trapped tissue may be rinsed thoroughly with saline or buffer. For very thorough cleansing, the outlet port is sealed, buffer is added, and the inlet port is sealed. The device is agitated to encourage thorough rinsing of the tissue, and then the device is held upright and the bottom outlet port unsealed to allow for drainage of waste or active suction of the effluent. This step can be repeated several times as necessary to achieve tissue that is highly “purified”. Finally, the washed tissue can be expressed from the inner flexible container by ‘rolling’ the tissue out through the inlet port (from bottom to top) into receptacles, e.g., syringes, for re-implantation or any other desired receptacle for further preparation before injection. Alternatively, a receptacle can be attached directly to the port such that the tissue can be anaerobically re-injected into the body.
While U.S. Pat. No. 6,316,247 to Katz et al discloses an improved device for harvesting and processing fat tissue during liposuction operations, it involves complex tissue cleansing operations, and handling operations which make it either impractical or undesirable in surgical environments.
Thus, there is a great need in the art for a new and improved method of and apparatus for safely harvesting, processing (i.e. preparing) and collecting adipose and other forms of tissue for immediate autologous tissue transplantation, explant culture endeavors or cell dissociations, while avoiding the shortcomings and drawbacks of the prior art methods and apparatus.